Other than just messing around with it, it really depends on the role you want to fill.  SharePoint is unique in that it covers ALOT of areas.  The main things is supports typically would otherwise fall onto a network admin or sysadmin, but alot of overlap also exists with developers and web programmers. 

However, SharePoint is also designed to take some of the pressure off the sysadmins and put it with other buisness positions, so it is fairly user friendly. The best advice I can give you is to put aside a whole day for install, and to grab yourself a book or read alot of Microsoft's documentation about setup. Once you have it up, you can just set up a sandbox for yourself and learn more.